This invention relates to conveying machines and more particularly to a splice for conveying machine guide rails.
Conveying machines generally include a moving belt or chain on which products are transported from one location to another. Guide rails are positioned along the sides of the moving belt or chain to keep the products from falling off the sides of the conveyor as they are transported.
Guide rails are commonly mounted on conveyors either by rigid fixtures or supports or by guide rail brackets. Guide rails are fabricated from a number of different materials and in various configurations. One guide rail design consists of an extruded plastic member deposed within a channel-shaped backing member formed of steel or stainless steel. The channel member includes a center section and side sections which are inclined inwardly for gripping the sides of the plastic insert and to facilitate gripping the guide rail for mounting on a conveyor. The Guide rails are preferably strong and stiff to resist side loading due to product back line pressure, but malleable enough to bend into various shapes to conform to the layout of the conveying system.
Such Guide rails are usually manufactured in ten to twenty foot lengths. As a result, the guide rail sections must be joined or spliced together wherever they meet so as to form a continuous guide rail system that provides smooth guidance of the product being conveyed. In the past, such joints were often formed by the use of a press-fit splice plate or backing plates fixed to the backside of the guide rail by welding or threaded fasteners. Press-fit splice plates were not wholly satisfactory because they did not exert sufficient force to hold the Guide rails together during surging of the product. Also, significant vibration exists in conveying systems, which tends to vibrate guide rail splice plates apart. As a result, the joint between two butted guide rails often open, resulting in damaged, downed or lost product. Moreover, fastening guide rail joints with welded back plates or threaded inserts is not only labor intensive but also expansive.